International Patent Application Publication WO2011/051828 discloses a support frame for a vehicle having an elongate hollow load bearing support member, the support member being generally horizontally disposed in relation to a support surface for supporting a load to be conveyed. The support frame includes mounting means for mounting the support member to the suspension frame assembly of the vehicle. The hollow support member is internally segmented to define a plurality of stowage compartments for stowing one or more types of transportable goods, preferably flowable substances, in use.
German Utility Model Publication DE202007001455U1 discloses a frame, in particular for a trailer, comprising an upper part designed as shell with integrated axle bearings. The longitudinally positioned upper frame part is made of a metal sheet bent into a unit open at its lower side. A king pin is located at the front for joining the trailer to a pulling vehicle. Three pairs of extensions extend vertically from the lower side of the frame and can be used as axle bearings. Transverse support elements are inserted between each pair of extensions.
U.S. Pat. No. 8,857,893 discloses a chassis, which generally comprises two I-beams spaced apart by plural cross members. A dual-axle bogie is positioned toward the rear of chassis and a square-legged extendible landing gear is positioned toward the front of chassis, aft of the kingpin to which a heavy duty truck tractor can be pivotally secured. Two cross beams are also provided on which a container may rest during transport. Landing gear permits the chassis to sit level and allows elevation of the chassis so that a tractor can be attached to and detached from the chassis.